TR6- And So It Begins

[suzook12]

Unit 650, Triumph added a ninth bolt through the head into the block between the cylinders on the exhaust side. 750 upgrade kits have the thread in the block for this.

73 on 750, Triumph added a tenth bolt through the head into the block between the cylinders on the inlet side.

Afaik, increasing a Triumph twin's capacity beyond 750 is not done by increasing the bore i.d.:-

. early 73 750 are 75 mm bore, barrel casting thickness is increased near the base to allow 76 mm;

. practically, increasing a Triumph twin's capacity beyond 750 is done with a Norton 89 mm stroke crank.

I have been doing some research on this and I think the order of the day is build what I have now, maybe utilising 750 pistons as looks like it needs a rebore anyway, and collect a pile of parts to turn it back to an all alloy motor as they come up at reasonable price rather than being held to ransom......

 

[Rudie]

maybe utilising 750 pistons as looks like it needs a rebore

Watch the spigots at the bottom of the block are not left too thin ... they can crack and drop off ...

 

[suzook12]

they can crack and drop off ...

Story of my life that!!

 

[suzook12]

Parcels have started arriving already...... Never thought I'd see the day I was buying af spanners and sockets, must have binned hundreds of them over the years, whitworth too, all went..... Even the BA spanners I had went....

Cam and clutch pullers on route too

 

[suzook12]

Cam tools dropped today as well, hoping clutch puller will land tomorrow as well.

Gotta pick a scabby but triumph front end up tomorrow..... Coming along

 

[suzook12]

Bit further along today. Clutch now off and primary inner removed. Spat the rollers out of the clutch bearing as well. Guess thats going to be a nice time consuming job right there, cleaning and reassembling those.....

Engine is now ready to come out but will have to wait until next week now as busy with other stuff for a few days now. T100c should be arriving tomorrow

 

[Rudie]

Spat the rollers out of the clutch bearing as well. Guess thats going to be a nice time consuming job right there, cleaning and reassembling those.....

Stick each with a dollop of grease. Have a couple of spares in case you do not use a big enough dollop.

 

[suzook12]

Stick each with a dollop of grease. Have a couple of spares in case you do not use a big enough dollop.

Bagged up for now
Thanks for the offer.
Debating whether to go to Newark Sunday. If its cold as today was beside the M6, I wont be bothering

 

[suzook12]

Soooo Christmas, covid and a host of other things, including the T100C have got in the way of this. Was having a good old measure up to compare with the T100 to find out why the TR6 was sitting so low (post #28). Finally found it, the bolt on part of the frame is bolted through the wrong hole at the top, about an inch or so ahead of where it should be bolted...... Guess someone was looking for the "chop" effect.
Motor and box will be out over the next week, then get the frame off to the welders, shot blasted and primed ready for a slow dry build.

Been doing a lot of research on this over last few weeks, seems to all intents and purposes, it should be a dynamo engine, so it clearly has non matching crankcases. More and more a bitsa the more I look.... Not a problem. Onwards and upwards.....

 

[speedrattle]

non-bitsas are important to historical types and show people. for excellent reasons, for their purposes.

i bought my non-bitsa T120 forty-seven years ago and made it a bitsa almost right away. its my main motorcycle and the one i always pick on that first good day on the spring. more reliable, faster, and more fun as it is now rather than as it was new.

i have original stuff in the warehouse on the trickle chargers but they never get ridden as much as the bitsas.

 

[suzook12]

non-bitsas are important to historical types and show people. for excellent reasons, for their purposes.

i bought my non-bitsa T120 forty-seven years ago and made it a bitsa almost right away. its my main motorcycle and the one i always pick on that first good day on the spring. more reliable, faster, and more fun as it is now rather than as it was new.

i have original stuff in the warehouse on the trickle chargers but they never get ridden as much as the bitsas.

Quite agree mate, it is important to have historically correct examples, I believe it's also important to have period customs as well to show how things once were. But here we are, 67 years later and things have moved on. I have every intention for this bike to be a daily ride and reliable. Original enough to get it registered no problem, custom enough to make it useable.

So in that respect, being a bitsa is no problem, just needing to know what I have to start with....
The engine number tallies up as a 56 TR6, that should be a dynamo engine, but I have an alternator timing side crankcase, and I also have a dynamo primary cases. It has cast head and barrels with a single monoblock..... Am sure we'll get it all up and working

 

[speedrattle]

im building a bitsa right now with 1967 cases, a 70 crank and primary, either a 70 or 72 transmission, 69 T120 cylinder head, unknown rocker boxes, and timing gears from one of my big boxes. sorting the threads out took a while.

it goes into a 66 Tr6 frame fron section with a 65 rear section, oil tank, and battery box, 69 forks with latrer TLS brakes, a pre-unit rear wheel, and a tank from some old trident, they tell me.

looks good so far

 

[Rudie]

tank from some old trident
66 Tr6 frame fron section

If a Trident tank, no cutouts in the bottom for coils; studs or bolts through the frame front mounting, the hole in the tank's rear mounting does not line up with the thread for the bolt in a twin's frame.

69 forks

69 or 70 Trident or TR6R bottom yoke, with the extra metal at the back to restrict turning between the frame stops? Otherwise the fork legs hit the tank on full lock.

 

[speedrattle]

If a Trident tank, no cutouts in the bottom for coils; studs or bolts through the frame front mounting, the hole in the tank's rear mounting does not line up with the thread for the bolt in a twin's frame.


69 or 70 Trident or TR6R bottom yoke, with the extra metal at the back to restrict turning between the frame stops? Otherwise the fork legs hit the tank on full lock.

dunno, rudie. i had to abandone the original lower triple tree, as it was so badly bent. this is what i started with

heres some of the rest

i still have to go look at the triple tree and the tank. i believe the triple tree is okay if i drill out the front of the frame and install steering stem studs, but its -13C out there right now.

i have no experience with preunits, like suzook is working on. will be interesting to watch that prgress.

 

[Rudie]

believe the triple tree is okay if i drill out the front of the frame and install steering stem studs

Photo. would not enlarge very much but the frame steering head appears to have at least one stop - hanging down? If the other is/both are broken off, the remains should just unscrew from the steering head casting; then the thread is either 3/8"-26 or 3/8"-24 depending on the age of the frame. Remembered another way I have stopped fork legs or handlebars hitting the tank is to make stops with a larger diameter under the steering head.